Assemblies for making cable beads

ABSTRACT

In making a cable bead or grommet by rotating an annular bead, feeding to it strand from a coiled supply thereof and rotating the coiled supply of strand successively about the bead, an improved rotating assembly is described which rotates the annular bead at predetermined substantially constant velocity with respect to the axis passing through the centers of cross section.

451 Sept. 30, 1975 United States Patent 1191 2,339,762 1/1944 Bruestle............................., 2,438,448 3/1948 Morton et al.... 3,023,300 2/1962 [75] Inventor: Leslie L. Randall, Akron, Ohio Lehnert............ 3,289,304 12/1966 White....... ..226/173X [73] Monsanto Company, St. Louis, Mo.

June 11, 1973 3,606,810 9/1971 Kozij.'........ 226/173 226/173 226/173 Assignee: 22' Filed:

3,684,145 8/1972 Jenkins 3,690,534 9/1972 21 v Appl. No.: 368,860

Related US. Application ata Primary ExaminerC. W. Lanham Continuation-impart of Ser. No. 228,988,, Feb. 24,

Assistant ExaminerD. M. Gurley 1972. Pat. No. 3,805,852.

[57] ABSTRACT In making a cable bead or grommet by rotating an annular bead, feeding to it strand from a coiled supply [52] US. 140/71 R; 245/15; 226/173 [51] Int. B21F 45/00; B291-1 17/34;

B21F 37/00 140/88, 71 R; 57/21, 158; 245/15; 226/173; 425/450, 451, 455; 242/4 thereof and rotating the coiled supply of strand successively about the bead, an improved rotating assem- [58] Field of Search bly is described which rotates the annular bead at'pre- A, 4 B, 4 C, 4 R

I determined substantially constant velocity with respect to the axis passing through the centers of cross section.

[56] References Cited UNITED STATES PATENTS 1 570 821 1/1926 Beyea 57/21 9 Claims, 15 Drawing Figures 1,746,221 2 1930 226/173 Mattcson US. Patent Sept. 30,1975 Sheet10f13 3,908,713

FIGURE I U.S. Patent Sept. 30,1975 Sheet2of 13 3,908,713

FIGURE 2 U.S. Patent Sept. 30,1975 Sheet3of 13 3,908,713

MM IHIHI 44 52 j) 49 28 25 BI FIGURE 3 U.S. Patent Sept. 30,1975 Sheet 4 of 13 FIGURE 4 U.S.Patent Sept. 30,1975 Sheet5of13 3,908,713

FIGURE 40 US. Patent Sept. 30,1975 Sheet60f13 3,908,713

FIGURE 4b US. Patent Sept. 30,1975 .Sheet70f13 3,908,713

FIGURE 5 U.S. Patent Sept. 30,1975 Sheet80f 13 3,908,713

I I T I J. I j I I I I I I I I I I I I I I I I I I II IIIIIIIIIIIIII 1111;:

j L FIGURE 6 [03 I030 US. Patent Sept. 30,1975 Shet9ofl3 3,908,713

m mmzmzm o 0 l P B MEDOE U.S. Patent Sept. 30,1975 Sheet 10 0f13 3,908,713

FIGURE l3 US. Patent Sept. 30,1975 Sheet 11 of 13 3,908,713

VON

VON

mmnwl US. Patent Sept. 30,1975 Sheet 12 of 13 3,908,713

MEDOE 9m NNN mN NNN NON :N 2% N 9N NNN mON NNN mNN O N mNN wow mON mON 2N U.S. Patent Sept. 30,1975 Sheet 13 of 13 3,908,713

MEDOE MON ASSEMBLIES FOR MAKING CABLE BEADS This application is a continuation-in-part of application Ser. No. 228,988 filed Feb. 24, I972, now US. Pat. No. 3,805,852, the entire disclosure of which is incorporated herein by reference. This invention relates to an apparatus for making cable beads or grommets particularly for pneumatic tires.

BACKGROUND OF THE INVENTION Cable beads or grommets comprising an annular core of wire covered by several spirals or convolutions of strand wire were described early in the art. A characteristic of the type of cable bead wherein the core is independent of the spiral wrap or strand is that imposi- .tion of a bursting stress on the cable will cause the convolutions of the spiral to grip the core tightly and the uniform distribution of stress throughout the cable provides great strength. Such beads are especially desirable for radial tires.

Prior methods of making cable beads have taken var ious forms but generally depart from making beads strictly of the aforesaid type and thereby compromise some of the desirable properties. One method is to use a continuous piece of wire for both the core and strand, the wire being wrapped upon itself under sufficient tension to distort it and bend it to lay tightly on the core. Another method is to subject the strand wire to a precrimping or spiraling operation and then wrap the prespiraled wire without further distortion. Both methods are to an extent self-defeating with respect to achieving maximum gripping action of strand wire upon the core when the bead is subjected to bursting force. In either case, the method of manufacture has comprised storing a supply of strand in coil form, feeding strand to the core while rotating the core and the coiled supply about the core, and if necessary, providing suitable means to avoid twisting of strand.

For the manufacture of cable beads having high gripping action, it has been found desirable to minimize bending distortion of strand in the process of feeding it to the core. Apparatus heretofore described which moves a coil of metal strand around the core in a circular path, introduces substantial bending of the strand, especially at points where the supply is furthermost from the plane of the core, although movement in a cirproper relationship.

SUMMARY OF THE INVENTION The improvements, according to this invention, re-

late to a system which includes supporting and rotating an annular core or bead about its axis of symmetry and feeding strand to the core from a coiled supply while rotating the coiled supply of strand successively about .the core with respect to an axis passing through its centers of cross section and rotating the coil about its own axis to compensate for the rotation about the core. The improvements comprise rotating the annular core and ensuing cable bead at predetermined substantially constant. velocity with respect to the circumferential axis strand and the frictional force exerted by the rollers passing through the centers of cross section of the core by means of an improved bead drive assembly.

It will be appreciated that one or several layers of strand may be applied to the core. Each layer of strand is usually wound opposite that of the previous layer. According to the usual convention a 1 9 cable indicates a core with a single layer of 9 strands. Thus, a cross section of the cable would comprise a central core surrounded by 9 strands. Similarly, a l 8 15 20 cable indicates a central core covered by 8 strands and having in addition another layer of 15 strands and finally an outer layer of 20 strands. The core may comprise single or multiple units. The process of manufacture starts with an annular hoop, herein referred to as a core or bead, to which strand is applied to produce the desired cable bead. The core and strand are usually metal and the strand is usually circular in cross section but the method and apparatus are adaptable to wrap material which is flat or ribbon shaped and to materials other then metal. The process will be described for application of single continuous units of strand to form each layer but similar principles are applicable to feeding more than one unit of strand at a time.'

The improved assembly for imparting predetermined, substantially constant velocity to the rotation of the annular bead 'with respect to the axis passing through the centers of cross section of said head em ploys gripping means which exert opposing pressure against the bead with respect to its plane of symmetry. The jaws of the gripping means are held against the side of the bead by spring pressure and are movable not only to release the completed bead and to insert a new core for the next bead, but are movable while under the said spring pressure in order to accommodate the growth of the bead as strand is applied. The diameter of a cross section of the bead parallel to the axis of symvaries and tends to allow slippage.

To apply pressure evenly regardless of surface irregularity, the jaws of each gripper or each pair of grippers may be individually spring loaded with one jaw pressing against one side of the bead and its opposite member pressing against a corresponding area on the other side of the bead. The adjacent pair of jaws being individually spring loaded willaccommodate variations of the bead surface around its circumference. However, a

simpler construction which accommodates surface variations without individual spring loading of the grippers has the gripper jaws staggered, as hereina ter described, so that the opposing forces are at different or staggered locations on the circumference of the bead. In either case, by driving at the sides of the bead, the effect of the changing circumferences of the annular bead around its axis of symmetry is minimized. A positive drive in which the same area of the bead surface remains in frictional contact with the surface of a gripping jaw throughout the span of contact reliably provides substantially constant veleocity of the circumferential axis of the bead through its centers of cross section during the entire formation of the bead regardless of the layers of wrap applied.

DESCRIPTION OF THE DRAWINGS FIG. 1 is an elevation of an apparatus for manufacture of a cable bead viewed perpendicular to the plane of the bead.

FIG. 2 is an elevation of the same apparatus viewed parallel to the plane of the bead.

FIG. 3 is a plan view of the same apparatus showing the drive means for the rotating platform and the position of the wrap supply.

FIG. 4 is a plan view of the gear box which controls the motion of the wrap supply.

FIG. 4a is a cross section at line AA of FIG. 4 viewed in the direction of the arrows showing the arrangement of gears for driving the wrap supply and maintaining it in proper orientation.

FIG. 4b is a cross section at line BB of FIG. 4 viewed in the direction of the arrows showing the detail of the wrap supply mounting.

FIG. 5 is a front view (perpendicular to the plane of the bead rotation) of an improved assembly for rotating the bead.

FIG. 6 is a side view of the same assembly.

FIG. 7 is a view of the chain gripper assembly perpendicular to the plane of rotation.

FIG. 8 is a detail of a gripper unit.

FIG. 9 is a front view (perpendicular to the plane of the bead rotation) of another embodiment of an improved assembly for rotating the bead.

FIG. 10 is a layout of the embodiment of FIG. 9.

FIG. 11 is a cross-sectional view along path 11-I1 of FIG. 9 selected to illustrate the principal working parts.

FIG. 12 is a cross section on line 12-12 of FIG. 9 illustrating the means for spreading apart the clamping plates to release the bead.

FIG. 13 is a detail of two adjacent grippers of FIG. 9 viewed perpendicular to the plane of the bead rotation.

DETAILED DESCRIPTION A device for making cable beads in which the improved rotating assembly may advantageously be substituted is illustrated in FIGS. 1-4b. The device comprises three mechanical assemblies, namely, motor drive assembly, bead holding and rotating assembly, and reel carriage assembly each of which performs a separate function. The motor drive assembly comprises a gear motor which supplies power through separate gear and power transmission systems to the bead rotating assembly and to the reel carriage assembly. The bead holding and rotating assembly of FIGS. 1 and 2 comprises a series of guides and rubber faced rollers on both the inside and outside diameter of the bead. Rubber faced rollers on the outside of the bead are paired to rubber faced rollers on the inside of the bead, the outside series being mounted on swing arms which are actuated by air cylinders to open and close. The reel carriage assembly comprises a rotating slotted platform with a reel or canister to hold the wrap wire mounted on a pivot shaft and gear box. The rotation of the platform and pivot shaft the angular disposition of the pivot shaft impart a complex motion to the reel,

In FIG. 1, the apparaus with the core andstrand in place is illustrated in its condition at the beginning of the manufacture of'a cable bead. An end of the wrap wire or strand 1 is fed to the core 3. To start the operation the end of the wrap wire may be secured to the core by Mylar tape or other suitable means adopted for keeping the end of strand against the core. A supply of strand in coil form is wound on a reel or confined in canister 4 mounted on rotating platform 5 supported on post 2. Opposite the strand supply and its mounting assembly, which includes an angle gear box indicated generally as 6, is counter weight 7. The bead holding and rotating assembly comprises grooved guides 8 and 9 and five pairs of rubber faced idler rollers 10, 11, 12, 13 and 14 on the inside of the bead or core and driven rollers 15, 16, 17, 18 and 19 on the outside of the bead or core. The inside rollers are mounted with their centers in an arc such that their faces form an are equal to the inside radius of the cable bead to be formed. The outside rollers are mounted on swing arms pivoting around shafts 20, 21, 22, 23, and 24, respectively, the pivot motion being controlled by air cylinders, one of which 25 is visible as part of swing arm assembly in housing 28, to open and close (clamp or release) the cable bead. The control switch 29 for the clamping assembly is located in the operator control panel 27. Upon actuating starting switch 26 in operator control station 27, the core and ensuring bead continuously rotate in the direction of the arrow over the aforesaid rubber faced rollers. A jog switch or button 30 activates the drive only when depressed permitting small adjustments to be made in the position of the bead or core which may be desirable at the beginning and end of the operation. The continuous forward motion is terminated by activating stopping switch 26a. Grooved guides 8 and 9 in conjunction with the rubber faced rollers keep the rotating bead in a vertical plane. Grooved rotary guide 8 is mounted on a swing arm assembly controlled by an air cylinder, not shown, and grooved rotary guide 9 is stationary mounted. The assembly which drives the bead comprising the aforesaid grooved guides, driven rollers, pivot shafts and air cylinders is mounted on a suitable frame or top weldment 31.

The power is supplied by gear motor 32 which drives two sprockets on shaft 33 which in turn drive chains 34 and 35. Chain 34 drives a positive variable speed gear box or transmission 36 by means of sprocket 37 on the gear box. The output of the gear box is transmitted by sprocket 38 via chain 39 to the bead drive assembly. Chain 39 drives a sprocket on shaft 24. A gear, not shown, mounted on the same shaft meshes with a gear on the shaft bearing roller 19 driving it in a counterclockwise direction. Another sprocket, not shown, on shaft 24 drives a chain to a sprocket on shaft 23. An additional sprocket and chain and a gear are mounted on shaft 23. The chain drives shaft 22 by a sprocket mounted thereon, and the gear meshes with a gear on the shaft on which roller 18 is mounted. Similar sprockets, chains and gears drive the remainder of the shafts and driven rollers. The variable speed gear box serves as a synchronizer by which the ratio of the bead speed to the reel carriage speed can be adjusted as required.

The gear motor 32 also drives the rotating platform 5 on which the reel canister is mounted by aforesaid chain 35 to sprocket 40 of reversing gear box 41. The output of the reversing gear box is transmitted by sprocket 42 and chain 43 to sprocket 44 driving rotating platform 5. Sprocket 44 acting through an angle held in engagement with sprocket 56 on the platform FIG. 2 is an elevation of the same apparatus viewed 2 parallel to the plane of the bead. Into base weldment 45 are mounted the gear motor 32, reversing gear box 41, and variable speed transmission 36. Chain 35 transmits power from the reversing gear box to drive the rotating platform 5. The platform contains a slot 47 for loading and unloading the bead. The reel canister 4, shown in its position furthest removed from the bead, is tipped at its maximum angle toward the core. Power is transmitted via chains 35 and 43 to sprocket 44 which in turn serves to drive the rotating platform through angle gear box assembly 52 to sprocket 53 which drives chain 54 (FIG. 3) and sprocket 56. Power to the bead drive assembly is transmitted by chains 34 and 39 to sprocket 48 mounted on shaft 24 in the top weldment 31. On the same shaft is mounted a gear, not shown, which meshes with a gear on the shaft on which roller 19 is mounted. Sprocket 48 on shaft 24 and chain 39a drive sprocket 48a on shaft 23. Sprocket 48b also on shaft 23 and chain 39b drive sprocket 480 on shaft 22. Sprocket 48d on shaft 22 and chain 39c in turn drive a sprocket on shaft 21 (FIG. 1). A detail of the bead drive and clamping assembly is shown in relation to roller 17. Gear 49 on shaft 22 meshes with gear 50 shown by phantom lines on shaft 51 on which shaft roller 17 is mounted. Gear 50 and shaft 51 are mounted in housing 28a pivotally mounted on shaft 22. The operation is controlled at operator conrol station 27.

FIG. 3 is a plan view of the platform drive assembly showing drive means for rotating the platform and the strand supply supported thereon about the bead. Sprocket 44 through angle gear box 52 drives sprocket 53 and chain 54 which passes around idler sprocket 55, chain 54 thereby being maintained in contact with platform sprocket 56 driving the platform in clockwise or counterclockwise direction as desired. On the side of the platform opposite counter weight 7 is angle gear box 6 protruding from which is a shaft on which drive sprocket 70 is mounted. A chain 57 around sprocket 70 and idler sprocket 58 engages stationary sprocket 59 mounted on the platform support post 2 (FIG. 1). As the platform rotates, say in a counterclockwise direction, drive sprocket 70 must also travel a circular path with respect to the axis about which the platform rotates. The chain 57 engaging stationary sprocket 59 is thus forced to move to permit the platform to rotate in turn forcing sprocket 70 to rotate in a clockwise direc? tion. The rotation of drive sprocket 70 is transferred through a gear train (FIGS. 4, 4a and 4b) in the angle gear box 6 to the shaft (FIG. 4b) on which the reel or canister is mounted so that the reel or canister remains in the same relative position throughout the cycle in the sense that wrap wire 1 feeds out of the canister slot 60 to the bead 3 in the same direction with respect to an axis thereof. A section of the top weldment 31 has been cut away to show a portion of the bead drive clamping assembly, including air cylinder 25, housing 28 and gear 49.

FIG. 4 is a plan view of angle gear box 6 showing the general arrangement of the gear train which controls the motion of the reel canister. The operation of the gear train will be clearer from FIG. 4a which is section AA of FIG. 4 viewed in the direction of the arrows. Drive sprocket powers bevel gear 61 which meshes with bevel gear 62 on shaft 63. On shaft 63 is also mounted helical gear 64 meshing with helical gear 65 on shaft 66 on which shaft is mounted the supply of wrap wire. This arrangement serves to maintain the reel of canister in the same orientation with respect to the cable bead in the sense that a horizontal line representing the diameter of the reel canister taken parallel to the plane of the rotating platform is always parallel with the plane of the core.

The annular mounting for the wrap supply coil will be apparent from FIG. 4b, a cross section of FIG. 4 on line BB viewed in the direction of the arrows. The gear box body 68 is bored at an angle to receive shaft 66 terminating in mounting flange 67 integral therewith. In a typical case, the angle will be about 30 from the vertical. Shaft 66 rotates in bearings 69 and 69a. When the reel canister is inside the core and 180 therefrom, the planes of the reel canister and of the core coincide, but the reel canister will be tilted toward the core. At from the aforesaid position, the bore hole in the gear box body will be directed at the same angle toward the core, but due to a 90 rotation of the reel canister, it is the plane of the reel canister which will be tilted toward the core. Due to the simultaneous rotation of the reel canister. The pitch of the plane of the reel canister to the plane of the bead varies from 0 to 30 to 0 in each half revolution of the rotatable platform.

An improved assembly for rotating the core and ensuing bead is illustrated by FIGS. 5, 6, 7 and 8.

FIG. 5 is a front view, front being considered perpendicular to the plane of the core, of a core and bead rotating assembly which clamps the core and bead by a series of grippers which exert force perpendicular to the plane of the core. A series of gripper assemblies, 100, are mounted on an endless chain 101 driven by a sprocket 102a on shaft 102. The chain passes around idler sprockets 103a mounted on shaft 103. The shafts together with the sprockets and chain which they carry are supported in a housing comprising housing plate 104 and a corresponding plate, not shown. Plate 105 is supported by four rods, 106, which pass through the housing and are secured to a back plate (FIG. 6) on which rods springs are mounted. To plate 105 is attached plate 107 by cap screws 108. An air cylinder 109 serves to apply air pressure to relieve the spring pressure to release the bead.

Further details of the assembly are apparent from FIG. 6 which is a side view showing the alternate series of grippers in disengaged position for clamping the core or bead. The staggered grippers 100 within plates 107 are held against the bead by spring pressure exerted by a series of springs 110. The springs are between plates 111 and 112. Plate 111 is rigidly fixed by four rods 106 to plate in the sense that, although not adjacent to one another, their relative positions are fixed by the rods. Said rods pass through plate 112 which plate floats on the rods. Secured to plate 1 l2 and plate 105 by cap screws, not shown, are curved plates 107. Said curved plates are tapered outward at each end to receive the series of grippers and bring them to bear gradually against the bead. Plates 107 are desirably somewhat thicker at their outer periphery but only in the tapered portion to provide a lead-in ramp.

The chain mounted staggered grippers 100 between plates 107 are forced firmly against the bead by the aforesaid springs and drive the bead as they move through the pressure are. When a gripper leaves the area of plates 107, it immediately disengages and is forced away from the bead by a small torsion spring 121 to the maximum outward position and remains in this condition until it again enters the area of plates 107 and comes under the influence of the strong spring loading pressure. Of course, as each gripper leaves the pressure area, another enters it so that the bead remains under the pressure of substantially the same number of grippers. To remove the bead, air cylinder 109 is actuated and drives plates 107 apart against the spring loading pressure. Small springs, not visible, between front fixed plate 105 and front housing plate 104 and between floating plate 112 and the rear housing plate 104 provide a self-centering system permitting the grippers to adjust to the precise position of each particular bead.

FIG. 7 is a view of a typical gripper chain asembly. A standard chain attachment 113 supports each gripper unit comprising a base block 114 (FIG. 8) secured by rivets 115 to the chain attachment 113. The base block contains three horizontal holes one at each end and one in the middle, the end holes being adapted to receive one pin 116 (FIG. 8) of a standard chain connecting link 117. It will be appreciated that only one connecting link is secured to each base block, the position depending on which side of the bead the gripper is intended to engage but to further the interchangeability of parts, a hole is provided in each end. The other pin 1 16a of the connecting link engages the body of the gripper jaw 118 by means of a similar hole. The gripper jaw is therefore free to pivot through a limited are around pin 116 of the connecting link in the base block. In the maximum closed or engaging position, the gripper jaw body rests on base block 114.

In FIG. 7, connecting link 117 is near its maximum open position, as would be the cage at the end of making a cable bead. In the maximum closed position, the inner face is coincident with the center of the base block. The maximum open position, assuming no restraint by the spring loading pressure, is limited by the restraint of the base block exerted when the gripped jaw body contacts the base block in its outward motion away from the core or bead. However, during the time a gripper jaw is under the pressure of the spring loaded plates, it is of course thereby restrained. Two hardened steel rollers or ball bearings 1 19 mounted in the gripper jaw body provide the contact areas between the gripper and plate. These rollers permit the gripper jaw to move smoothly past the spring loaded plate in spite of the strong pressure exerted thereon. A neoprene or other rubber insert 120 in the gripper jaw body contacts the bead and grips it securely.

Once the gripper jaw passes by plate 107 and is no longer restrained thereby, a small torsion spring 121 forces it to its maximum outward position. One arm of the spring contains a 90 bend and is inserted in a small hole provided in pin 116a of connecting link 117. The coil of the torsion spring is supported by a stud 122 mounted on plate 125, and the plate is secured to the base block 114 by means of a screw, not shown, in the center hole thereof. The other arm of torsion spring 121 is restrained by a stud or spacing member which is part of the aforesaid plate 125. A flange or key on the bottom of plate 125 flush with the bottom of the base block extends part way across the bottom of prevent twisting of the plate with respect to the base block. Each of the series of staggered gripper jaws is of similar construction.

FIG. 8 is a side view of one of the gripper assemblies. Standard chain attachment 113 is mounted on base block body 114 secured thereto by two rivets 175, one of which is not shown. Pin 116 of standard chain connecting link 117 engages the base block 114, and pin 116a engages the body of gripper jaw 118 in which is mounted hardened steel rollers 119. Plate 125, secured to the base block by a screw, supports the coil of torsion spring 121 by stud 122 about which it is free to rotate. The arm of the torsion spring which contains a bend is inserted in a small hole provided in pin 116a.

Ideally, strand is applied to the core under the natural spring tension of essentially straight strand in contrast to the aforementioned known method in which the strand is deliberately subjected to sufficient tension to cause permanent distortion which bends it to lay tightly on the core. Any permanent curvature is desirably less than the curvature of the core to which it is applied and if the available strand wire has been subjected to too much strain, it may be treated to reduce the distortion before applying it to the core. Methods for killing wire strand are well known. Moreover, the improved bead drive assembly disclosed herein permits incorporating treatment to reduce distortion in the process of applying strand. Reducing some of the strain in the process of applying strand is feasible because of the reliability of the positive drive assembly. Of course, means must be provided to restrain the strand supply in coiled form and in the case of an unshrouded or open reel, a braking means must be provided in any event to prevent unwinding of the reel due to the spring tension of the strand.

The strong pressure of the coil springs is highly concentrated at the relatively small areas of contact between the core and gripper jaws. Although the driving assembly must not only rotate the core and ensuing cable bead but must pull the strand from the supply, the powerful gripping forces assure substantially constant velocity of the core even when pulling strand from a small tensioned reel, say a 3-inch reel carrying nominal 0.06 in. diameter strand and through means to reduce curvature of the strand. Accordingly, a tensioned, small open reel may advantageously be adopted. Tensioned reels on apparatus for making grommets have been described by Beyea U.S. Pat. No. 1,570,821, Jan. 26,. i 1926 and by Hansen et al. U.S. Pat. No. 2,753,678, July 10, 1956. However, means for taking up slack described by Beyea is not necessary due to the herein'described angular mounting and as indicated, no reel shroud is needed on a braked reel.

Another advantage of the improved core and bead driving assembly is that it allows the means selected for holding the starting end of strand against the core to pass through the unit. The gripping area adjacent to the starting end will maintain the end of strand in fixed relation to the core throughout the arc of the pressure area without interfering with or disturbing the means for keeping the end from flopping away from the core after it leaves the pressure area.

A more rugged, smoother running embodiment of the rotating assembly which holds a constant radius through the pressure arc is illustrated in FIGS. 9-13. It provides a curved track recessed in supporting plates through which the carrier for the gripper assemblies moves to prevent skewing and assure that the gripper forces remain perpendicular to the plane of the core.

As seen from the front view illustrated in FIG. 9, a series of gripper assemblies 200 are mounted on an endless chain 201 (FIG. 10) comprising chain attachments 213 and connecting links 213a (FIG. 11) driven by sprocket 202a on drive shaft 202 (FIG. 10). The drive shaft assembly, better seen in FIG. 11, comprises drive shaft 202, drive pin 234, bearing 239 & 243, snap rings 237 and thrust washers 238. The chain passes around idler sprocket 203a mounted on idler shaft 203 (FIG. 10). The shafts, together with the sprockets and chain which they carry, are supported in a housing comprising front track plate 204, rear track plate 204a (FIG. 10) and spacer block 207. Grooves or tracks shown in FIG. 11 are recessed in plates 204 and 204a. These track plates which correspond to housing plates 104 of FIG. are attached to a spacer block 207 by four flat head screws 208. Four rods 206 (FIG. pass through the housing on which springs, as previously described, are mounted to exert clamping pressure which, in the present embodiment, is exerted on the grippers through front clamping plate 205 and rear clamping plate 205a (FIG. 10). The width between the clamping plates in open position may be varied by adjustment nut 211 and bolt 212. An air cylinder 209 shown in ghost lines is mounted in back of the assembly to provide means for forcing the clamping plates to open position. A chain tensioner 223 of hardened steel and springs 223a in a machined slot in the aforesaid spacer block keeps tension on the chain which moves the grippers. In this embodiment, each gripper jaw moves horizontally across the carrier instead of lifting off the carrier through an arc, as previously described.

FIG. 10 is a layout of the rotating assembly of FIG. 9, including air cylinder 209 in block 225 and clamping springs 210, viewed parallel to the plane of the bead rotation, herein generically designated as side position, and from the top. The piston rod of the air cylinder is extended by actuator rod 224 to which plate 205 is adjustably secured. Clamping plates 205 and 205a exert plates 105, 112 and 107 of the embodiment shown in FIG. 6. The carrier or base block 214 (FIG. 11) of the gripper assembly is guided through a curved path conforming to an arc of the bead by the aforementioned grooves in track plates 204 and 204a. Springs 216 between plates 204 and 205 and between plates 204a and 205a provide a selfcentering system which locates and maintains plates 205 and 205a so as to be uniformly spaced with respect to the center line between track plates 204 and 204a. The wrap point is in the center plane of the gripper drive assembly parallel to track plates 204 and 204a. Clamping plates 205 and 205a, being uniformly disposed with respect to said center plane outside the track plates, locate and maintain the driven bead in the center of the path of the wrapping strand. The bead rotating assembly in effect serves as a guide for one side of the bead and the wrap point for strand is desirably just prior to the point at which the bead enters the drive assembly. Drive sprocket 202a on drive shaft 202 and idler sprocket 203a on idler shaft 203 are fixed thereto by set screws 217. The drive sprocket drives endless chain 201 to which the gripper bodies 218 (FIG. 11) are attached by rivets 215. The gripper bodies comprise two portions as seen in FIG. 1 l which come together under the influence of pressure of clamping plates 205 and 205a overcoming the effect of compression spring 221. In one portion of the gripper body is mounted bearing 219 and in the other neoprene insert 220. As explained previously, four flat head screws 208 attach plates 204 and 204a to spacer block 207. Plate 205 is rigidly secured to rods 206 by screws 222. The rods visible are two of four supporting rods slidable through plates 204, 204a and 205a. Plate 204a is provided with means for attaching the entire assem-,

bly rigidly to a base supporting other mechanical assemblies of the bead wrapping machine.

Path 11-11 of FIG. 9 is selected to illustrate the principal working parts and a cross-sectional view thereof is shown by FIG. 11. Air cylinder 209 is secured to block 225 which in turn is secured to rear clamping plate 205a by cap screws 227. Plates 205 and 205a are shown in open position being forced apart against the pressure of clamping spring 210 by the pressure of air admitted to air cylinder 209 which, acting through actuator rod 224, exerts pressure on plate 205 forcing it to the left. Corresponding pressure is transmitted to block 225 and rear clamping plate 205a so that they, along with the air cylinder 209, move to the right across bushings 226 and plate 205 moves an equal distance to the left along with rod 206 to which it is attached by screw 222. On the other end of the rods, clamping springs 210 are retained by retaining washers 228 and screws 222a which replace plate 111 of FIG. 6. The aforementioned adjustment nut 211 and bolt 212 are shown in relationship to actuator rod 224 which controls the width to which the plate can be spread apart. With the plates in open position, cam roll 219, supported on roll pin 229, is pushed outward by compression spring 221 in a slot of the gripper body 218. Retaining cap 230 and retaining cap screw 231 unite the two portions of the gripper body and cover the slot for the compression spring 221 anchored by stop pin 232. Release of the air pressure forces plates 205 and 205a together under the clamping pressure of springs 210 uniting the two portions of the gripper bodies and sliding them across the face of gripper carrier 214 so that the neoprene insert 220 in the gripper faces engage bead 233.

The tracks or guides for the gripper assembly (driven portion) are clearly visible in FIG. 11. Cam rolls 219a mounted on shafts to gripper carriers 214 and secured by lock washers 240 and nuts 241 move through the grooves or curved track recessed in track plates 204 and 204a (not to be confused with plates 107 of FIG.

5. The gripper assembly which includes gripper carriers 214, rivets 216, chain attachments 213 and connecting links 213a is driven through the tracks by sprocket 202a keyed on drive shaft 202 by key 242 and is in turn driven by a power source, not shown, acting through drive pin 234 fitting into a female socket on the power source. The drive shaft rotates in bearing 239 in rear housing plate 204a and bearing 243 in front housing plate 204. Snap rings 237 on the drive shaft hold the shaft in position. Thrust washers 238 hold the inner and outer races of needle bearing 239 in which the shaft rides in rear track plate 204a. The track, recessed in plates 204 and 204a fixes the position of the gripper carriers 214 and the assembly of which they are a part when the grippers are under the pressure of plate 205 and 205a. When they move out of the pressure area it is sufficient merely to provide clearance for the cam rolls in the plates. A completely enclosed track is un' dersirable outside the pressure area in order to permit the proper functioning of the chain tensioner. The whole assembly for rotating the bead is secured to the rest of the bead wrapping machine by mounting screws 235 through plate 204a to mounting block 236.

The means for spreading apart the clamping plates to release the bead are shown in further detail by FIG. 12, a cross section of FIG. 9 on line l2l2. The screw fitting by which air cylinder 209 is fastened to block 225 in the embodiment illustrated is clearly visible as is the piston rod of the air cylinder extended by actuator rod 224 to move front clamping plate 205 to the left. As previously explained, the counter force moves rear clamping plate 205a, block 225, and air cylinder 209 an equal distance to the right. Further details of the chain tensioner are also visible. Spring 223a exerts its spring pressure on chain tensioner 223 over which glides chain 201.

Two adjacent grippers of the embodiment of FIG. 9 viewed perpendicular to the plane of the bead rotation are seen in FIG. 13. Two of the cam rolls 219a which roll in one groove of the recessed tracks are attached to one end of the gripper carrier and only one is on the opposite carrier, the arrangement on the adjacent carrier being just the opposite as shown by the ghost lines of the roller shafts. The number of rollers per carrier may be adjusted in accordance to the relative size of the carrier and rollers. However, using /2 in. rollers on carriers 0.968 in. wide, a convenient combination, makes it impossible to mount four rolllers on each carrier. As previously explained, the position of grippers on the carriers is alternated so as to stagger the direc tion from which they engage the bead. Thus, the roller 219 is visible on one and the neoprene insert 220 on the gripper face is seen on the adjacent unit.

Although the invention has been illustrated by typical examples, it is not limited thereto. Changes and modifi cations of the examples of the invention herein chosen for purposes of disclosure can be made which do not constitute departure from the spirit and scope of the invention.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as fol lows:

1. Apparatus for rotating an annular core and ensuing bead while wrapping strand around the core which comprises:

housing for supporting the apparatus,

means for attaching the housing to a supporting base gripping means which include movable grippingjaws to exert pressure against the bead from opposite sides of the plane of symmetry of the bead which contains its entire circumference and perpendicularly to such plane, for driving the bead at predetermined constant velocity supporting means for supporting each gripping jaw with respect to which each grippingjaw is independently movable toward and away from said plane of symmetry,

means for moving said gripping jaws on endless paths and all at the same velocity on the paths into and out of engagement with the bead surface said paths being arcuate over the portion in which the gripping jaws engage such surface, pressure applying means movable with respect to the housing for forcing the gripping jaws into engagement with the bead and maintaining pressure thereon characterized by automatic compensation means for allowing growth of the bead as strand is applied, such compensation means acting perpendicularly to the aforesaid plane of symmetry of the bead, and

means for separating the gripping jaws to insert and remove the bead.

2. Apparatus of claim 1 in which the pressure applying means comprise spring loaded plates tapered at each end.

3. Apparatus of claim 1 in which the gripping jaws are staggered to exert pressure against the bead at alternate areas on opposite sides of the plane of symmetry of the bead.

4. Apparatus of claim 1 in which the housing includes two plates of fixed relative position having a curved track recessed in each plate through which the gripping means are movable.

5. Apparatus for rotating an annular core and ensuing bead while wrapping strand around the core which comprises gripping means which include movable gripping jaws for exerting pressure against the bead from opposite sides of its plane of symmetry which contains the entire circumference and perpendicularly to such plane, for driving the bead at predetermined constant velocity housing for supporting the apparatus including two housing plates of fixed relative parallel position having a curved track recessed in the interior of each plate,

means for attaching the housing to a supporting base,

gripping jaw carrier means for supporting the gripping jaws movable through the curved tracks and affixed to an endless chain with respect to which carrier means each gripping jaw is independently movably toward and away from said plane of symmetry,

drive means for driving the endless chain, the gripping jaw carrier means affixed thereto and the supported gripping jaws such drive means moving all of the gripping jaws at the same velocity along the curved tracks,

pressure applying means including two clamping plates on spring loaded supports which pass through the housing, one clamping plate being affixed to the supports and the other slidable .thereon, said pressure-applying means being characterized by automatic compensation means for allowing growth of the bead as strand is applied, such compensation means acting perpendicularly to the face of said housing plates and to said plane of symmetry of the bead, and

pressure relieving means for forcing the clamping plates apart to relieve the pressure of the gripping jaws against the bead to permit insertion and removal of the bead.

6. Apparatus of claim 5 in which the gripping jaws are horizontally movable across the gripping jaw car- 

1. Apparatus for rotating an annular core and ensuing bead while wrapping strand around the core which comprises: housing for supporting the apparatus, means for attaching the housing to a supporting base gripping means which include movable gripping jaws to exert pressure against the bead from opposite sides of the plane of symmetry of the bead which contains its entire circumference and perpendicularly to such plane, for driving the bead at predetermined constant velocity supporting means for supporting each gripping jaw with respect to which each gripping jaw is independently movable toward and away from said plane of symmetry, means for moving said gripping jaws on endless paths and all at the same velocity on the paths intO and out of engagement with the bead surface said paths being arcuate over the portion in which the gripping jaws engage such surface, pressure applying means movable with respect to the housing for forcing the gripping jaws into engagement with the bead and maintaining pressure thereon characterized by automatic compensation means for allowing growth of the bead as strand is applied, such compensation means acting perpendicularly to the aforesaid plane of symmetry of the bead, and means for separating the gripping jaws to insert and remove the bead.
 2. Apparatus of claim 1 in which the pressure applying means comprise spring loaded plates tapered at each end.
 3. Apparatus of claim 1 in which the gripping jaws are staggered to exert pressure against the bead at alternate areas on opposite sides of the plane of symmetry of the bead.
 4. Apparatus of claim 1 in which the housing includes two plates of fixed relative position having a curved track recessed in each plate through which the gripping means are movable.
 5. Apparatus for rotating an annular core and ensuing bead while wrapping strand around the core which comprises gripping means which include movable gripping jaws for exerting pressure against the bead from opposite sides of its plane of symmetry which contains the entire circumference and perpendicularly to such plane, for driving the bead at predetermined constant velocity housing for supporting the apparatus including two housing plates of fixed relative parallel position having a curved track recessed in the interior of each plate, means for attaching the housing to a supporting base, gripping jaw carrier means for supporting the gripping jaws movable through the curved tracks and affixed to an endless chain with respect to which carrier means each gripping jaw is independently movably toward and away from said plane of symmetry, drive means for driving the endless chain, the gripping jaw carrier means affixed thereto and the supported gripping jaws such drive means moving all of the gripping jaws at the same velocity along the curved tracks, pressure applying means including two clamping plates on spring loaded supports which pass through the housing, one clamping plate being affixed to the supports and the other slidable thereon, said pressure-applying means being characterized by automatic compensation means for allowing growth of the bead as strand is applied, such compensation means acting perpendicularly to the face of said housing plates and to said plane of symmetry of the bead, and pressure relieving means for forcing the clamping plates apart to relieve the pressure of the gripping jaws against the bead to permit insertion and removal of the bead.
 6. Apparatus of claim 5 in which the gripping jaws are horizontally movable across the gripping jaw carrier means into and out of engagement with the bead surface, the pressure of the clamping plates is exerted on the gripping jaws through bearings and the gripping jaw carrier means are movable on bearings in the recessed track.
 7. Apparatus of claim 6 which includes springs between the housing and clamping plates for self-centering.
 8. Apparatus of claim 7 in which each gripping jaw has an elastomeric face for interfacing with the bead and the gripping jaw carrier means are a series of gripper carriers each of which carries a single gripping jaw which approaches the bead from a direction opposite to that from which each adjacent gripping jaw approaches the bead.
 9. Apparatus of claim 5 in which the housing plates are secured to a spacer block, the spring loaded supports for the clamping plates are rods slidable through the housing plates and the movable gripping jaws are staggered to exert pressure at alternate areas on opposite sides of the bead surface. 